Chicago goes through LOOP therapy

A crane lifts materials into place as crews work to rebuild the CTA’s “L” track structure in downtown Chicago. Photo courtesy of RailWorks.

CTA and its contractors work to overhaul 30-year-old track components in the heart of one of North America's largest cities.

Chicago wouldn't be the world-class city that it is without the familiar rumble of the Chicago Transit Authority (CTA) "L" trains resonating within the city's Loop, an area bordered on the north by Lake Street, east by Wabash Avenue, south by Van Buren Street and west by Wells Street. CTA calls the elevated Loop "L" the heart of its rail system, with five of its eight rail lines and an average of 684 trains traveling through it every weekday. Track components in this area of the system dated back to the early 1980s and were nearing the end of their useful life. Preemptive maintenance measures were required, as any delay encountered in the Loop would negatively affect the overall rail system.In 2012, the $33.8 million Loop Renewal Project began to replace track components within the Loop and at the two busiest junctions on the CTA's rail system. The project was one of the largest the CTA had planned during the past few years and is part of Mayor Rahm Emanuel's Building a New Chicago program, which is updating infrastructure deemed critical to the city.

The project was a complete renewal of the elevated track from the steel structure on up and included replacing special trackwork, installing close to 11,500 feet of 115-lb. rail, replacing wood crossties, tie plates and other smaller track elements and replacing Tower 12 and Tower 18 interlockings.CTA, along with the project's general contractor, Ragnar Benson, trackwork contractor, RailWorks Track Services and traction power and signal contractor, Meade Electric Company, Inc., utilized good communication, precise planning and expert coordination to complete the project over the course of 13 54-hour weekend work windows and two nine-day windows.

Project challenges

There were several elements endemic to the Loop "L" that presented project challenges including working on top off the 35-foot elevated structure, a dense urban environment and compressed work windows.According to CTA, material delivery times played a major role in determining the order that work was to be completed.

"The contractor began replacing the standard tangent section first. The Wells/Van Buren Curve, new crossovers and special trackwork at Tower 12 were completed later in the project," said Catherine Hosinski, CTA media representative. "CTA coordinated work at Tower 18 and Hubbard Curve with the Wells Street Bridge work during two nine-day extended line cuts this past spring."

While material delivery dictated work priority, delivering that material on site presented its own hurdle and one that Eric Goetschel, RailWorks area manager, said was solved by working with the CTA.

"You're working 35 feet in the air in the middle of Wells and Van Buren downtown and have to get material and manpower up and down all weekend long. There were few spots on the job where you could put 80-feet of rail or a crane and get the materials up to the site," said Goetschel. "We relied heavily on the [CTA]. They've done work in the area and were able to steer us in good directions."

In addition to the construction challenges, CTA also had the operational challenge of maintaining rail service and executing a project within a dense urban environment.Hosinski explained, "As with all CTA construction projects, every effort is made to lessen the impact on customers, neighbors and public transit services. During this project, construction work was primarily limited to weekends, with the majority of the work completed under rail system reroutes.

"In general, trains would undergo reroutes in the Loop on Friday nights (e.g. trains operating only on the inner Loop track or outer Loop tracks), then on Saturdays and Sundays, work resulted in full closure of portions of the elevated track in the Loop, along with respective street closures. During work that required line cuts (termination of service) - bus shuttle service was provided."

Hosinski says the contract included a constraint that the new double crossover at Washington/Wells had to be installed prior to the line cuts for Tower 18, which allowed CTA to maintain modified Orange Line service from Midway Airport into the Loop during the line cuts.

"The basic outline of the coordination was that CTA's Loop Track project included four weekend line cuts for Tower 18 and two weekend line cuts for Hubbard Curve work," said Hosinski. "By combining this work with the two nine-day extended line cuts needed for the [Wells Street] bridge - CTA reduced the impact to customers."CTA also focused on limiting the impact of the work on local businesses within the construction zone. Hosinski says CTA and the general contractor worked closely with the Chicago Department of Transportation (CDOT) to coordinate and plan street closures for the work and, with help from CTA Government and Community Relations, the general contractor was able to make accommodations for nearby residents and businesses that were impacted by project work.

Safety factor

Maintenance work always calls for strict safety protocols, but when you move that work two stories above street level, extra precautions are needed."We had to constantly monitor the changing conditions and keep a safety program up-to-date throughout a weekend because things change and we had to change with it," said Goetschel.

While Ragnar Benson, RailWorks and Meade Electric were responsible for developing safety plans specific to each contractor's work, they also coordinated with one another on safety.

"[RailWorks was] basically the middle of the operation, we had [Meade Electric] taking down the third rail in front of us, then we stripped the track and built the track and then Ragnar Benson followed up putting in the walkways and the hand rail systems, so everyone utilized the same plan throughout a weekend, but it was ever changing based on conditions and locations," said Bill Dorris, vice president and general manager of RailWorks.

Because of the compressed work windows and tight work spaces, RailWorks built a 30-foot long model of the Loop "L" standard track structure to prepare for the project. The model not only aided in establishing a safe work environment, but helped in developing an efficient workflow, as well.

"We had pretty good detail on the model to look at and get a good understanding of what we were dealing with and how the sequence and replacement was going to happen each weekend," said Dorris. "It was our first attempt at doing something like that, but I think it was a good idea, a good practice and it served us well."As Goetschel told "RailWorks Today," the company's employee newsletter in November 2012, "You get one or two chances to get everything coordinated the right way and if you don't, you're going to fail in what you were trying to do. Having the model to use ahead of time gave everyone perspective on how they were going to accomplish the work."

Coordinated effort

"Proper coordination and planning was critical for this project," said Hosinski.

She points to the collaborative efforts between the CTA and CDOT to schedule and plan project work that would affect the roughly 40,000 people who traveled across the Wells Street Bridge on an average weekday via CTA rail service as one of the most notable achievements of the Loop Track Renewal project.

"While CDOT was in the design phase of the Wells Street Bridge Reconstruction project, CTA and CDOT coordinated a plan to combine work on the 90-year old Wells Street Bridge with work that was currently under contract on the Loop Track Renewal Project," said Hosinski. "This resulted in two nine-day closures of the bridge in early March and again in late April, which also halted CTA's Brown and Purple line service into the Loop. Because transit service was significantly impacted, CTA provided extensive service alternatives for affected train passengers, which also required extensive planning and coordinating across multiple city agencies."

While CDOT performed work on the bridge, CTA was able to rebuild the track junction at Lake and Wells Streets, known as Tower 18 and performed track renewal in the curves at Hubbard and Kinzie, just north of the Merchandise Mart.

"By performing this work simultaneously, CTA was able to reduce the duration of the work by eight days and reduce the number of street closures and service disruptions. Additionally, combining the work helped save CDOT and CTA $500,000 in construction coordination costs," said Hosinski.

Goetschel and Dorris of RailWorks believe the project's success from their perspective is tied to the support received from the CTA, Ragnar Benson and Meade Electric.

"The amount of work that had to get done during [the weekend work window] and the real tight access area, especially Tower 18, you always stood back Sunday night watching everything go back together in amazement that you could get that work done in a weekend," said Goetschel.